A teenager was plied with whisky and shown pornographic videos by an older man who went on to take part in sexual acts with him, a jury has heard.

David Beard, 64, who had befriended the boy, allegedly sexually assaulted him for two years when he was a teenager in the 1980s.

Beard, of Gladstone Way, Cambridge, who was a science teacher at the time, has denied two offences of indecent assault on a male under the age of 16.

The jury at Cambridge Crown Court heard that the alleged victim had been ashamed at what had happened and did not report it, but decided to take action after reading a report that Beard had been acquitted of sexual activity with another young man in a separate court case.

William Carter, prosecuting, said the boy first got to know Beard in the 1980s when Beard was in his 30s.

He said Beard had also run a mobile disco which the boy was interested in.

“Mr Beard befriended him and over time invited him to his house where he was sexually abused,” Mr Carter said.

He told the court that Beard offered the boy whisky and told him he had a pornographic video upstairs.

“He asked whether he wanted to go up and watch the video and he was not averse to going upstairs and watching pornography,” Mr Carter said.

He told the court that sexual activity took place between Beard and the teenager in the bedroom where the boy was said to have found a photograph of a naked child.

The court heard that sexual activity continued for a number of months.

Mr Carter said the boy did not report what had happened when he was younger and came to feel it had been wrong.

“He was feeling guilt and shame himself and didn’t want others to know what had happened,” Mr Carter said.

He said the alleged victim’s mental health was fragile and he subsequently opened up to his girlfriend.

He also told a relative and later mentioned what had happened to a mental health worker who contacted police.

Mr Carter said the alleged victim had been doing some research on Beard on the internet and saw that he had been found not guilty of a similar offence and decided that he had to do something.

He told the court that Beard had been arrested and denied giving the boy whisky or showing him a pornographic video.

Mr Carter said Beard categorically denied any sexual offences had taken place.